package com.tangqiang.threedes;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class ThreeDES {

	private static final String Algorithm = "DESede"; // 定义 加密算法,可用 DES,DESede,Blowfish

	// keybyte为加密密钥，长度为24字节
	// src为被加密的数据缓冲区（源）
	public static byte[] encryptMode(byte[] keybyte, byte[] src) {
		try {
			// 生成密钥
			SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);

			// 加密
			Cipher c1 = Cipher.getInstance(Algorithm);
			c1.init(Cipher.ENCRYPT_MODE, deskey);
			return c1.doFinal(src);
		} catch (java.security.NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (javax.crypto.NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (java.lang.Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	// keybyte为加密密钥，长度为24字节
	// src为加密后的缓冲区
	public static byte[] decryptMode(byte[] keybyte, byte[] src) {
		try {
			// 生成密钥
			SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);

			// 解密
			Cipher c1 = Cipher.getInstance(Algorithm);
			c1.init(Cipher.DECRYPT_MODE, deskey);
			return c1.doFinal(src);
		} catch (java.security.NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (javax.crypto.NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (java.lang.Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	// 转换成十六进制字符串
	public static String byte2Hex(byte[] b) {
		String hs = "";
		String stmp = "";

		for (int n = 0; n < b.length; n++) {
			stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
			if (n < b.length - 1)
				hs = hs + "";
		}
		return hs.toUpperCase();
	}

	public static void main(String[] args) {
		// 添加新安全算法,如果用JCE就要把它添加进去
		// Security.addProvider(new com.sun.crypto.provider.SunJCE());

		final byte[] keyBytes ={ 0x11, 0x22, 0x4F, 0x58, (byte) 0x88, 0x10, 0x40, 0x38,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; 
//			{ 0x11, 0x22, 0x4F, 0x58, (byte) 0x88, 0x10, 0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD, 0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,(byte) 0xE2 }; // 24字节的密钥
		String szSrc = "This is a 3DES test. 测试";

		System.out.println("加密前的字符串:" + szSrc);

		byte[] encoded = encryptMode(keyBytes, szSrc.getBytes());
		System.out.println("加密后的字符串:" + byte2Hex(encoded));

		byte[] srcBytes = decryptMode(keyBytes, encoded);
		System.out.println("解密后的字符串:" + (new String(srcBytes)));
	}

}